1. Technical Field
The present invention relates in general to computer networks, and in particular, to a network processor for managing network traffic that uses an internal frame format containing layer specific control information.
2. Description of the Related Art
Computer networks have evolved to a point where switch routers are insufficient to handle complex network routing and filtering requirements. Network processors, such as the International Business Machines (IBM) Network Processor (NP) have been developed to fill this need. Utilizing a connection similar to that of a network switch, an NP provides a level of control and flexibility that surpasses that of the network switch. Parallel lookup operations can be performed on a frame, complex modifications can be performed on packets, and policies can be managed at complex levels. Multiple processors are used to achieve a very high frame processing throughput.
Instructions for managing frame routing in an NP, known as xe2x80x9cpicocode,xe2x80x9d reside in memory but are directly used by the hardware to efficiently process frames according to a fixed set of rules. The rules are entered by administration software and compiled into picocode that drives the logical engines for controlling frame routing, frame filtering and Quality of Service (QoS) requests.
The NP also provides media interfaces for connecting standard network interfaces and routing media interface frames between ports and between the media interfaces and a switch fabric. Frames received by the network processor may be of varying types. The network processor forwards L2, L3 and L4 frames. These labels are according to the Open Systems Interconnect Reference Model, developed by the International Standards Organization (ISO), wherein L2 refers to a data link layer such as Ethernet, L3 is the network layer such as Internet Protocol (IP), and L4 to a transport layer such as User Datagram Protcol (UDP) or Transmission Control Protocol (TCP).
The present disclosure provides an improved method for processing frames by embedding layer-specific control information within frames routed within the NP, so that processing may be simplified, producing a resulting increase in performance.
The objective of processing frames by embedding layer-specific control information within frames routed within a NP is achieved in a method and system for processing frames in an NP. The NP receives a frame at an input, determines a layer type of the frame and embeds appropriate control information within a modified frame. The frame is then routed to an appropriate layer processing component within the network processing system. The frames may be discarded by a layer based on filtering criteria. Layers may also be bypassed if a layer determines that one or more layer processors will not be performing processing on the frame.
All objects, features, and advantages of the present invention will become apparent in the following detailed written description.